Electron tube



June 28, 1949. P. G. cHEvIGNY ELECTRON TUBE 5 Sheets-Sheet l Filed Jan. 26, 1946 1N VEN TOR. P//Z/L G. C'l/f WGW Y A TTOIPNE'Y .Fume 2, 1949.

P. G. CHEVIGNY ELECTRON TUBE 5 Sheets-Sheet 2 Filed Jan. 26, v1946 m SSG.. W. u

June 28, 1949. P. G. cHEvlGNY ELECTRON TUBE 5 Sheets-Shaml 3 Filed Jan. 26, 1946 A Tmp/wy Patented June 28, 1949 ELEoTRoN TUBE Paul Georges Chevigny, Paris,

France, assigner to Federal Telephone ,and ,Radio Corporation,

New York, N.

Y., a corporation of Delaware 'I Application January 26, 1946, Serial No. 643,787

(Cl. Z50-152.)

1,6 Claims. 1

This invention relates to electron beam-producing apparatus, particularly of the type .suitable for use as -electronic distributors, and to the method of manufacturing same.

Electronic distributors for distributing energy to a plurality of channels, usually to selected ones of said channels, have been suggested for use in various lmultiplexsystems such as for .ex-

ample, in the .copending application of E. M. Deloraine for Communication system, Serial No. 628,613, led November 14, 1945. In the Deloraine system, signals are translated into amplitude-modulated pulses. These amplitudemodulated pulses are given a predetermined amount of delay corresponding to the channel to which they are directed. An electronic distributor is employed to distribute these pulses to the selected channel, the amount of delay determining the channel.

The distribution is accomplished by providing in said distributor, means Ifor rotating an electron beam, as in .a cathode ray tube, and mounting in the circular path -of the beam, a yplurality of target yelements which are connected to Idifferent channels. Normally the beam -is cut off as by applying a suitable cut-off voltage 4to the control element 4ofthe distributor. As the beam-rotating means operatesto set up varying fields which would .rotate the beam, signa-ls arrive and are impressed upon the -control element to raise its potential above cut Ioff and cause the beam to :dash on. The instantaneous .fields .then existing by virtue of theA operation 'of the beam-rotating means, direct the beam to one of the vtarget elements and produce a Apulse in the channel associated with said element. Since the beam-rotating eldsvary continuously and cyclically, the particular target element elected by a given pulse depends onthe time of arrival of the pulse or, stated another way, depends on the amount of delay of the pulse with respect to a given reference.

Where a limited number of channels are employed and therefore a limited number of target elements are required within one distributor, as for example, .a hundred, it is feasible to arrange the target elements in .a single .circle which is scanned by the rotatable electron beam. Where,

lhowever, .greater numbers of such elements are required, this arrangement-.becomes impractical.

An object of the xpresent inventionI is the -provision of improved electronic beam-producing apparatus of the typefhereinabove described.

.Another v'object is'fi'fhe provision .of :such ,ap-

2 paratus having anovel arrangement vof .the .target elements.

Another object is the provision in such ap.- .paratus .of a ,very large number of .target elements.

Another object is the provision `of such an .apparatus .in .which the .target .elements are .sep- .arated from .each other -by shields .to minimize interrerence .or cross-.ta'lk between the various channels.

Further objects .are the provision .of 4an improved method formaking electronic beamepro- .ducing apparatus .of the general .type .referred .to hereinabove.

Qtherand iurthercbjects of .the .presen-,t in vention will become apparent. and .the invention will be best..-understood from .the .following de-.- scription of embodiments thereof,.reierence lbei-ng had to .the drawngs,..in which.:

Fig. 1 is .a =diagrammatic .representation .oran electron beam-producing .apparatus .in accordance with my invention; l

Fig. 2 is a cplanriew ofthearrangementofthe .target elements duringonestep Iin the process .of manufacturing .theiapparatusfolig c1; i

Fig. 3 is .a plan viewof .oneefrthe shie1ds. .inter posed between .the .targetelements in fthe ap'- .paratus of Fig. 1; I

Fig. 4 is adiagrammatic representation -of Va modified form .of .apparatus fembodyingf-lmy invention; and

Fig. 5 is asimilar lView ofianothermiodication. n

Referring now to Fig. 1, .the .apparatussthere illustrated, includes .a [form LoLcathode .ray ltube I :having an .envelope withinwhich =is.mounted toward one .end thereof `a conventional type of electron Vgun-3 including a control element. orgrid 4 to which energy, inthe form. of. pulscs,'fwhich are to bedistributed'in accordance .with their time of 1arriva1,.are. ated over linevli. Atia .distance from. .theigun I3, there are arranged.. conventional horizontal ,and vertical .defiecting :plates L6 which are connected over apair .of lines to .a itwo-y phase generators!! .which serves ato. .produce .a ro-- tationof .the .electronbeam i9 which passes :between .saiddeecting 1plates .when-.vansincoming pulse arrives .along Sline 5. Thel two-phase gen-l erator `8 .may lbe synchronized. l)from .any1 ksuitable source. At .the iexpanding...portion offithestube envelope .2, .there isarranged .a toroidally-shaped produce a magnetic eld -whichicurves :the elec-i wherealong theglength of the..envelope lthe-.beamil.Wilt.inripinge..uponitheL hereinafter-described target elements. Current is supplied to toroidal-deflecting coil Il) by a stepped saw-tooth generator II which produces a saw-tooth output composed of steps, as shown in wave-form I2, to change the layer or tier of target elements upon which the beam impinges. The saw-tooth generator II is synchronized with the two-phase generator 8 over line I3, so that after each complete rotation of the beam produced by the two-phase generator 8, generator II increases the energy supplied to coil I by a single step.

The target elements may be arranged in the form of a plurality of rows or tiers I4 longitudinally spaced from each other along the tube envelope, with a plurality of annular metallic shields I5 interleaved between successive tiers. Each of the tiers consists of a plurality of metallic target elements It which elements may be in the form of short wires or rods which extend radially and are circumferentially spaced from each other and sealed in the glass wall of the envelope 2. The construction of this portion of the cathode ray tube may be best understood from a description of the method of making it.

Referring now to Fig. 2, a wire l'l in the form of a circle having a diameter greater than the diameter of the cathode ray tube envelope at which the target elements are arranged, has welded thereto, at spaced intervals, wire elements I8 which are somewhat longer than the target elements I6 but which are subsequently cut down as will be described hereinafter to leave portions which become the target elements It. The short Wires I8 are radially arranged and circumferentially spaced along circular wire I1. A large number of Wires may be so arranged as for example, a hundred. The assembly I9 thus produced permits handling of the Wires I8 as a single unit. As many assemblies I9 are provided as there are to be tiers of target elements in cathode ray tube I. In the embodiment illustrated, there are ten tiers. A similar number of shields I5 are also provided. The shields I5 consist of a't disks, as illustrated in Fig. 3, each having a large central opening. The disk shields I5 and the assemblies I9 are alternately stacked one above the other with annular glass rings in between. A high frequency coil or other heating means is employed to heat the glass as for example, preferably by inducing a high irequency current in the disk shields l5, which serves to fuse the glass between the disk shields as well as around the assemblies I9. After the glass has been Well fused about the disk shields I5 and the elements I8, it is gradually allowed to cool. The stacking of the assemblies I9 and shields I5 is so made that each of the circular wires I1 and the outer portion of the short wires I8 protrude beyond the disk shields I5. The circular wires Il and the outer portions of the Wires I8 are next cut o, thereby leaving the target elementsl It sealed through the glass rings 2B. The disk shields I5 and the longitudinal wires I8 are preferably made of an alloy having the proper coefficient of expansion so that when subjected to heat, the seal between these and the glass will not be broken. Various types of chrome-iron alloys are known for this purpose, such as for example, that known by the trade name of KovarJ The stack of disk shields and assemblies is then sealed to the rest of the tube envelope, as depicted in Fig. 1 toward the end thereof opposite the electron gun, with an end piece 2I of glass sealed to one end 22 of the stack 4 and the other end 23 of the stack sealed to an enlarged portion 24 of the envelope.

In the operation of the apparatus of Fig. 1, the strength of the magnetic field produced by the toroidal coil II] may be initially sufficient to bend the beam 9 so that it is directed toward the rst row of target elements nearest end 22 of the stack. The beam is then rotated for one complete revolution by means of the deflecting plates 6 actuated by the two-phase generator 8. Upon the completion of this single complete revolution of the beam, the saw-tooth generator operates to increase the energy supplied to coil I0 and causes the beam to impinge on the second row of target elements. The beam is then rotated for one complete revolution on the second row, whereupon another step increase in energy is applied to the toroidal coil ID which shifts the beam to the third roW of target elements from end 2'2. This is continued until the beam has scanned all the target elements of each row up to the end 23 of the stack whereupon the energy supplied to the coil I0 abruptly drops as shown in waveform I2, thus redirecting the beam toward the rst row of target elements at end 22 of the stack.

In the embodiment of Fig. 4, the use of the magnetic Icoil I0 is dispensed with by making the target elements 25 of gradually increasing length from end 23 progressively toward end 22 of the stack. The disk shields 26 are likewise of progressively increasing length, this being accomplished in the embodiment illustrated by welding to the inner ends of the disk 26 additional disks in which the central opening is of progressively decreasing diameter, from end 23 toward end 22 of the stack.

The apparatus of Fig. 4 also includes the electron gun 3 with control grid 4 and deflecting plates t. The grid 4 is controlled by the signal coming in over line 5 and the deecting plates 6 are supplied with two-phase voltages from the two-phase generator 8 to produce a rotation of the beam. To move the beam from row to row of target elements, the stepped saw-tooth generator Il is also employed but it is arranged to feed the two-phase generator with periodically stepped voltages so that the output of the twophase generator is periodically increased, thereby producing an increased deflection of the beam 9 in its circular path so as to shift the beam from row to row of the target elements.

In the embodiment of Fig. 5, the electromagnetic field coil I0 is also dispensed with and the deecting plate 6 and the electron gun 3 may be controlled as illustrated in Fig. 4. The shields 26, together with their added disks 2l, are similar to those in Fig. 4 and the gradually increasing length of the target elements measured radially from the center of the tube increase progressively as do the lengths of the target elements 25 in Fig. 4. However, at the inner end of each of the target elements 28, there is an additional portion 29 bent at right angles and extending longitudinally of the tube substantially parallel to the longitudinal axis thereof, the end 30 of each of said portions 29 facing the beam 9 and being adapted to be impinged upon by said beam. All of the ends 3E) dene a curve, all points of which are equi-distant from the center of the deflecting plates E so that the beam travels an equal distance to any of the rows of the target elements.

The beam 9 rotates in the embodiment of Fig. 5, as it does in the other embodiments, and as, in the embodiment of Fig. 4, the radius or diameter of the circle made by the end of the beam is varied to move the :beam from one row of target elements' to the next.

While'I have described the beam as moving from row to row of target elements beginning near end 2-2 and moving toward end 23 of the stack, it will. be obvious that the Ibeam may move in the opposite direction, namely, from near end 23 towardend 22..

Furthermore, while I have described the apparatus of Figs. 1-'5 as being used to distribute energy from lone source to a plurality of loads, it will be apparent that it may be used 4for various other purposes. For example, such apparatus may be used as a pulse generator by having the beam .continuously on and connecting all the target elements together to a common line. As thebeam 9 sweeps from target element to target element, pulses will be produced in said line and a large number of pulses will be thus produced at 'each complete travel of the beam from element to yelement and from row .to row. Various other .uses will occur to those versed in the art from thefhereinabove description and from the description of the aforementioned application of E. M. Deloraine.

Accordingly, while I have described above the principles of my invention in connection with specic apparatus, and particular modications thereof, it is to be clearly understood that lthis description is made only by way of example and not as a limitation on the scope of my invention as dened in the accompanying claims.

I claim:

1. Electron beam-producing apparatus comprising means for producing an electron beam, a plurality of rows of target elements arranged in the path of said beam, each row consisting of a plurality of target elements spaced in a plane transverse to the plane along which the rows are spaced, and beam-deecting means for deflecting the beam to impinge upon the target elements.

2. Electron beam-producing apparatus according to claim 1 further including shield means in the form of disks interposed between successive rows of target elements.

3. Electron beam-producing apparatus comprising means for producing an electron beam, a plurality of rows of target elements adapted to be impinged upon by said beam, each row consisting of a plurality of target elements arranged in the form of a circle, and means for deecting the beam to impinge upon the target elements of each of said rows.

4. Electron beam-producing apparatus comprising an envelope, an electron gun positioned toward one end of the envelope for producingr an electron beam, a plurality of rows of target elements supported from the Wall of the envelope at longitudinally-spaced intervals thereon and approaching the other end thereof, each of said rows of target elements consisting of a plurality of target elements arranged in the form of a circle, means for producing a circular sweep of the electron beam, and for varying the angle of deflection of the beam from the path it would take if undeilected so as to determine the row of target elements upon which the beam' impinges.

5. Electron beam-producing apparatus according to claim 4 further including a plurality of disks having central openings therein and serving as shields, sealed into the envelope between the rows of target elements.

6. Electron beam-producing apparatus according to claim 4 wherein said target elements are in the form of short wires sealed through the envelope and'lextending radially. ofthe. longi-I- tudinal axis of the envelope, saidYwires"beingfcil: cumf-'erentially spaced.

7. Electron beam-producing apparatus accord# ing to claim 1w-herein said target elements-are in the form of short wires sealed throughthe wall of the envelope and extending radially A of the central longitudinal .axis thereof, said target-ele ments being circumferentially spaced, durther including shielding means interposed between the rows of target elements, said shielding l'means consisting of flat disks sealed through-the envelope wall and having .central openings therein.

'8. Electron beam-producing apparatusl according to claim' 4 wherein said last-mentionedmeans includes an electromagnetic toroidal coil -arranged outside the envelope between the electron gun and the target elements, and means for :sup-

plying to said coil -energy periodical-ly varying in small abrupt steps.

9. -Electron beam-producing apparatus 'accord'- ing to claim 4 wherein said target :elementstare in the form of short wires sealed through-the envelope :and extending radially of the 'centr-ail axis thereof with the target elements ol. each yrow to the longitudinal axis of the envelope with the sealed portions extending radially of said axis, and the sealed portions of the target elements within each row being circumferentially spaced from each other, and the sealed portions of each target element in succeeding rows being progressively longer, the portions parallel to the longitudinal axis being also progressively longer in each succeeding row so that the ends of said lastmentioned portions are all substantially equidistant along the dcilected beam.

11. An electron distributor comprising acathode ray tube including an envelope, means for producing an electron beam within said envelope, a plurality of annuli arranged transversely with respect to the beam path, a plurality of target members arranged along the path of said beam and each forming part of a respective one of said annuli, beam deecting means associated with said beam producing means forproducing a circular sweep of the electron beam, and means including a stepped saw-tooth generator for varying the deection of the beam from the axis about which it sweeps to cause it to impinge upon the various target members.

12. An electron distributor according to claim 11 wherein said last-mentioned means includes an electromagnetic toroidal coil arranged outside the envelope between the electron gun and the target members, said generator being coupled to said coil for periodically varying the energy supplied to said coil in small abrupt steps.

13. An electron distributor -according to claim 1l, wherein said beam deflecting means includes two pairs of oppositely-disposed spaced deiiecting plates between which said beam passes, the energy supplied to both said plates being controlled by the stepped saw-tooth generator.

14. An electronic distributor including a cathode ray tube having an envelope, anv electron gun positioned toward one end of the envelope for producing a narrow, electron beam, a plurality of rows of target elements supported from the wall of the envelope at longitudinally-spaced intervals thereon and approaching the other end thereof, each of said rows of target elements consisting of a plurality of target elements arranged in the form of a circle, the beam being so narrow that it is adapted to impinge substantially entirely on one of said target elements at a time, means for producing a circular sweep of the electron beam, and means for varying the angle of deiiection of the beam from the path it would take if undeflected so as to determine the row of target elements upon which the beam impinges.

15. An electronic distributor according to claim 14 wherein said means for varying the angle of deection of the beam includes a toroidal coil arranged adjacent the path of the beam to set up a toroidal electromagnetic field thereabout, and a stepped saw-tooth generator supplying energy to said coil.

16. An electronic distributor according to claim 14 wherein said means for producing a circular sweep of the electron beam includes two pair f spaced deflecting plates arranged at right angles to each other and between which the beam passes, and a two-phase generator coupled to said deflection plates to produce a circular sweep of the beam, and wherein said means for varying the angle of deflection of the beam includes a stepped saw-tooth generator controlling the magnitude of the output of said two-phase generator.

PAUL GEORGES CHEVIGNY.

REFERENCES CITED The following referenices are of record in the fue of this patent:

UNITED STATES PATENTS 

